Concrete consistency meter



March 27, 1945. G. MAXON, JR 2,372,595

CONCRETE CONS ISTENCY MEFER Original Filed Aug. 6, 1941 5 Sheets-Sheet l March 27, 1945. 5 MAXQN! JR Q 2,372,595

CONCRETE CONSISTENCY METER Originai Filed Aug. 6, 1941 s Sheets-Sheet 2 43 '43 I ML March 27, 1945. G. MAXON,'JR

CONCRETE CONSISTENCY METER 3 Sheets-Sheet 3 Original Filed Aug. 6, 1941 3 E/QHWE New]? J g Patented Mar. 27, 1945 CONCRETE CON SISTENCY METER Glenway Maxon, Jr., Milwaukee, Wis., assignor to The T. L. Smith Company, Milwaukee, Wis., a corporation of Wisconsin Original application August 6, 1941, Serial No. 405,580. Divided and this application May 15, 1943, Serial No. 488,016

6 Claims.

Glenway Maxon, Jr., Serial No. 405,580, filed August 6, 1941, now Patent No. 2,342,749, granted February 29, 1944, of which this application is a division.

As described at length in said parent application the consistency of concrete and other semiliquid mixtures can be determined from the shift in their center of gravity as they are being mixed in a rotating drum. This is accomplished by taking reactions at two spaced supports for the mixing drum and utilizing these reactions to produce two forces, one of which is obtained by means responsive to the weight of the batch as manifested in the reactions at said two supports, the other by means responsive to change in the location of the center of gravity as manifested An expedient manner of translating the reactions into the two forces and comparing the forces to effect an indication is by means of the hydraulic system disclosed in said parent application and which constitutes the subject matter of this invention.

It is to be understood, however, that while the invention here presented grows out of the concrete consistency meter covered in the aforesaid parent application, it is not limited thereto, but rather contemplates the general utility of the system.

One of the objects of this invention thus resides in the provision of a hydraulic system for translating force reactions into indicator motion which is adapted for use with consistency meters for measuring the consistency of concrete and other semiliquid mixtures.

Another object of this invention is to provide a hydraulic system of the character described which is so designed and constructed as to insure utmost accuracy in the translation effected thereby.

To this end it is a further object of this invention to provide a mechanism which is sufficiently rugged to maintain accuracy in spite of the hard usage to which it may be subjected.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate several complete examples of the physical embodiment of the invention constructed in accordance with the best modes so far devised for the practical application of the principles thereof, and in which:

Figures 1 and 2 are similar diagrammatic views of a mixer apparatus having a rotatable mixing drum to illustrate the manner in which a shift in the location of the center of gravity of a batch being mixed is utilized through the hydraulic system of this invention to produce the motion necessary for effecting the desired consistency indication;

Figure 3 is a diagrammatic view of the complete system;

Figure 4 is an enlarged front plan view of the instrument or mechanism of the system at which the motion necessary to effect the desired indication is produced;

Figure 5 is a side view of the mechanism shown in Figure 4;

Figure 6 is an enlarged detail view illustrating the instrumentalities of a modified indicating mechanism for use in a system slightly different in application but the same in principle; and

Figure '7 is a fragmentary detail view illustrating the manner in which the motion produced as a result of a shift in the center of gravity may be employed directly to effect the desired indication.

Although the invention here presented is not concerned solely with concrete consistency measurement but covers the system and apparatus disclosed in the aforesaid parent application for general utility, for the sake of clarity it will be well to define the invention with relation to the consistency meter of the parent application.

In general terms the application of the invention to a concrete consistency meter consists in supporting the trunnions of the cradle in which the drum of a tilting mixer is suspended with its axis normal to the axis of the cradle trunnions, by means of hydraulic cylinders of the same size.

The reaction in each cylinder is thus directly proportional to the weight or load on the trunnion supportedthereby. If the center of gravity of the drum and cradle structure shifts due to lateral shifting of the batch in the drum, the proportion of the weight or load carried by the two trunnions and consequently the reaction in their cylinders changes correspondingly. This change in reaction thus can be util;zed to ascertain change in the center of gravity.

The location of the center of gravity of a batch being mixed in the drum (with relation to the loads on the two cradle trunnions) depends upon the lateral position of the batch in the drum; and this dependsupon the'consistencyof the batch. During mixing the batch is shifted laterally due to the tendency of the mixing action to cause the batch to follow the ascending side of'the-drum. This, consequently, shifts the load in the drum and carries its center of gravity. away from one cradle trunnion and towardthe other to an extent depending upon the consistency of the batch.

A wet, relatively fluid batch IObVlOllSl'YiiWlllzIlQl? be carried laterally as far .as a'zdry,-;stifierr;batch.

A shift in the center of gravity of the batch less than a predetermined amount which represents the desired consistency would thus indicate a condition; of excess wetness, While .ashiit in the center of gravityg'beyondthe amount which-"represents the desirediconsistency:wouldindicate a toosdry condition of thebatch.

The change-tin reaction inthe hydrauhc cylinders due to the shift inxthe centenot gravitysof the drum load .thusmay be utilized 'to'ldeterrnine and-measure the consistency of thezbatch ibein mixed.

Through "suitable mechanism these changesiin reaction in. the hydraulic;cylinders aregindicated to the operator. on :anrappropriate:gaugezor scale so that the operator risxat all timesicognizantuof the conditiona-ofithe-batch sin. thezdrum. Hence,

if the batchvis too dry orttoorwet hercaznseffect o the necessary .1correcticn .rbBfDI'e dumping the batch.

Through careful weighing of the aggregateaan effort is. made .to adhere as .closelysas possible to a desired consistency but as is well known-to those 40 skilled the art, there are many: conditions yvl'lich affect the consistency of :-.concrete and-mere weighingoi the a'ggregatesbe-ioreachargingsthe drum will not insure the maintenance; of any desired consistency. 1

Hence, this invention when applied uto aconcrete consistency meter is .of :great VaIuetW-the operator as it enables him tomake corrections even while the ba'tch' .i being mixed; so that-all of'the concrete delivered willmeet:thespeciiications. I

As stated; it is thereaction in the hydraulic cylinders which-support the cradle trunnions that is used to effect the desired indication. 'The'manner in which this is accomplishedperhap will be best understood from the diagrammatic "disclosures of 11 Figures land "2. "As illustrated in these diagrammatic disclosures" the-conventional tiltingmixer has its mixing "drumf'5 rotatab ly carried by a cradle I. Theopposite'end of. this cradle have 'trunnions 8 and?! bywhich the cradle 2-7.5 constitutes :the ibasis; 1.

of the cylinders and are connected to the trun- "the"cylinders illand II due to the weight of the rbatchiandttheshift-of its center of gravity are :reflectedin miniature in this mechanism.

Theiessential elements of the panto-graph mechanismare two small hydraulic cylinders I 3 and I4, the pistons I3 and I4, respectively, of which both react upwardly, in iconsequence .llGlElihBt WBiQl-lli of thedrum contentsas willappear hereinafter; and .two 1 other miniature cylinders i5 :and Hi, ithe pistons |=5"..and .-I-6', ..r,espectively, iof-which react to: the weight respectively carried by the triinnions -8. and 9,:iand inwa .manner to be heneinafitende- .scribedefi-ect. rockingmotion ofsa lever member I! about a fixed pivot I8.

c It is the .movement of this). lever -?member I! whichpnovides thet-motionfor. the iindicatormech anism by which .the location of =.thei-center- Jof -g'ravity and any shift therein and-.consequently the consistency -of .the batchis visually indicated. :As stated the cylinders on tthe pantograph m board. are. .of miniature proportions:as-:compared ..to the hydraulic cylinders. l I]. and I l. iIn-sactual practice, ,these cylinders :aie fiye-eighths iof era-n inch in. diameter, while :the: cylinders 10.531111: 1 l

.earesixsor-seven inchesiidiameter.

The pressure sides of. the cylinders .I Ilsand: IzI

...are,connected; to. theminiature cylinders on; the

,pantograph .board throughsuitable tubing. -Qne line I9 connects the pressure side oftheicylinder 10 with the miniature cylinders ;I3-.a-nd 1:5;While .145. a line .20 .connectssthe. pressure side of: thewcylin- ,der I I with the miniatureicylinders ld and-l6.

Elie-pistons.- I3" and l4 cf. theminiaturemylinders I3 and .14 both. reactinpwand'ly' against t'a counterweight platform 2I. v v

'Ihis counterweight ,platioizm is connected .thnough tugs or harnessa-strapsi21withwa1whifiietree 23 pivoted 8.52311 :24 to the deyerumenrberel 1. Hence, an upward .ipulL on the tugs ?22,i:un*.less A qpposedlipulls: the: :lever: member 1 I J .toi'th'erposition shown in Figure 1 at which the wh iiiletree hitch 24 is :in vertical :alignment .Lthei fixed .pivot I8. 7 a

Attention; issdirected to: the iiactrthat the pistons I 3' and M'tare exa'ctlycoaxial iand arecon- .60stra-ined tovertical motion on a iine passing through the fixed pivot I8.

I The pistons ,I5'11and'. I8"irrtheminiaturenylinders IB'and .lfiz-arezconnected :to the opposite-ends of the lever :member Ii! iby iiug and whifiietree .1 -connections 25 and 26,:respectively, so thatan upward force on these pistons acts on the lever .member 1 I t-imagmanner tending to impose a turnmg moment thereon, butxinasmuc'h was their forces are applied: on: iOppQSitB sides of the-fixed pivot I 8 movement; of thegleveiv member-depends upon :a differential in the; forces act'ing- 'o nthe ..p-istons I.5".-an,d l5. w 1 inasmuchas-enly the liyie lead,- ire; ,cf.therbatch andithe shift in its center 2f -ggi or'vthe:consistency measmeanssof screws or other fasteningsztottheuppen' end: of a. yoke 40 by which it: is; connected; to :the. pistonxrod or. rams I35 otthescylinder. I3:

Specifically; the; yoke .40.:consistszof a :discA-I E in whichtthe piston IOdlOI ram. I3? is threaded:.and two: spacediparallellarms 42 which?. extend up alongside the-:cylinder and carrylateralxextenshine on; theinupper. ends into-which thescrews 01'1'0131161. fastenings: serving to: hold: the; platform 21I to the:yokemrathreaded:

The hydraulic cylinders :I Ikand: I =I :andz-theminiature cylinders on the pantographzboard have; beenzdefined' asheing connected-by. pipe. lines; I 9 and JIIi'andiin'; thedescription.thusafan itrhas :been assumed: that. the: system. was; maintained:-v filled. with-liquid, specificallya oil.

Tozlnsure maintainingitheefluid{system fulland' torreplenish loss which may occur: past. the piss tons; suitable; make-up; apparatus is provided; 'Ihissapparatus may consisttot apump-:anda reservoir 46 connected withzeach oi=.thezmains.cyl inders; II). and: I I. Asgclearly showniin". HEM-e3, the. outlet of. each pump is connected. with: its respectivemain cylinder v through a suitable feed. line 41 in which a checkzvalvei48:1sinc0rporated; and. withithe. reservoir by meansnr areturn line 49 having a control valve 50-inserted therein.

The upper sideofeachzof the main cylinders is also connected. tothe=reseryoir through-a .return line-5 I a It is togbe understood, however, that .the fluid \in. this line 5 I is-nottunder pressure.

Theoperation of the make-upapparatus-may be: manual but. is, preferably-.- automatic. One manner. of. efiectingjhe. desirediautomatic opera, tion ofthe apparatus is. by means ofsa mechanical or other. connection (indicated by the numeral 50f in; Figure 3.). between. the. bearing. block offeach. trunnion or. aipart movable therewith and its associated. control valve Elli Through these. con.- nections. the valves 50 are closed, whenever the bearing" blocks descend beyond. a, predetermined;

limit; Hence, loss ofoil in, the fiuid'syst'emiand underthepistons" IN or i I I'-wi11"efiect closmeof the" valve 50* so that" the' constantlyop'era'ting pump will force oil past the check valve 48" into thesystem:

To iron out vibrations andtmomentary shocks caused by the shaking ofthe supportingframe of the mixerdue to loading-'01 discharging'an adj aeent' machine or any other vibration producing disturbance; each of the pressure lines lfl-" and M has a needle =valve-*52 or other-suitable constric-- tion orchoke incorporated therein;

Thezvibration ofthe mixer, however, does have a beneficial value as it insures :responserufthe-pis tons of theminiature cylinders-orrthe:pantcgraph board; notwithstanding the. 4 closeness: of" their fiti:

Themanner .in', which 2;: shift-inthezilocation'lofz the center of gravity; of the batchiinztherdrnm'. efliects rocking motion. of. the-lever: member; I'I; hasbeen described; Ithasalso-beennoted that its is-the movement. of. this lever: member. which accretion:

produces; th motionilreqnired to:.effect:.the:desired; indicationi. 'I hi'szmovement :may be; utilized; die rectly. asxshown in:Figure;-7 by merely attachingz a pointer 53 lto the lever. member." I I to: betmovem across-xaiscaler54%calibrated to aflordan indieas tion of: the consistency of: the batch.

Better. results, however, are obtainedibyctransa lating: the motion" of the: lever member I11) by; means of self-synchronous electrical. motion transmitting devices" such as Selsyn'. motors into. the --desired indicator movement, andin Figure 3 the applicatlon of thisform of motion transmissionzisillustrated.

Inthis instance, the outer end of 'the: levermember l-'l?is c0nnected mechanically to the=rotor=- ofa- Selsyntransmitter 55 which isconnected electrically with a- SeISynreceiVer-SBZ The re--- ceiveroperates thepointer 51 of a gauge indi-- cated I generally by the numeral 58 and'includinga sca1e--59 w-ith which the pointer cooperates; The consistency meter thus'fandescribed has been applied-to the tilting type of concrete mixer: The invention is; of course, also susceptiblefor usewith the non-tilting type of mixer such as used on pavers.

In' this case; as defined-in the parent application, one end of the cradle has afixed pivotal support while; its other end is" supported" bya' hydraulic cylinder. I'hiscylind'er; likethe cylinl ders" It-and I'I, istpivoted to the supportingbase,

while its ram or pistonv rod connects with the freegend 'ofTthe cra'dle'so' that a load" on the'cr'adle applies :pressure on the fluidin the cylinder.

A load on the piston of" the cylinder. is thus. manifestedby an upward'reaction in a miniature cylinder. BOT with w-hichthe cylinder is connected through asuitablepipe line BI.

The miniature cylinder. 60 forms part. of; a,

pantograph. mechanism. indicated generally by.

thenumeral 62' and which in. addition tel-the; cylinder 60 includes another similar cylinder; 63- and-alevermember- 6.4 .lpivoted to-the panel board oLthe' mechanism astat' 65-w-hichpointis in line. withl-theaxisof the cylinder 60.-

Thelever member 64-isof triangular: forma: tion as previously described; andzthe ram or: piston ofzthe cylinder 63 is; tied; to the outer end: of the lever member through a tug andwhifl'tetree connection: 66', while the" piston or. ram of the cylindenfiilis tiedito the upper end'fof the lever member through a tugand whiffletree' connec tion- 81.

The miniature cylinder 63 isconnectedwith a reaction cylinder (not shown) through a pipe line 68" so that pressurein the latter cylinder effects an upward reaction in the cylinder- 63': Themanner-- in which the reaction cylinder is mounted so that the reaction" therein". is proportional-to the torque-load on the drive pinion of the mixer" forms no part' ofthe invention covered here. It' is adequately, illustratedandl d8:- scribed'in' the parent application. For thepurposes of this invention it is sufiicientto notethat, as in the previously described. embodimentof I the. invention, the dead weight and. the..f.riction. load are. cancelled. out intheir effect. at the pantograph. board... To. this-enda weight. 69=is carriedon a -counterweightplatform J0 supported; by the pistonof the cylinder-.60',- and.a weight 'II'isca-rried on alplatform:12;.supportedby the. piston of the cylinder 63.

The: pantograph: lever member 64 is thusleft urement, the effect of the dead weight of the drum, its cradle and associated mechanism should be cancelled out. This is conveniently accomplished by a weight 21 on the counterbalance'platform 2| which balances the weight of the empty drum, its cradle and associated mechanism. The effect of the dead load on the pistons 15' and I6 is also subtracted or cancelledout by counterweights 28 and 29 supported by the pistons l5 and I6, respectively.

In the purely diagrammatic and illustrative follows that the load on the two trunnions is not the same. Hence, the counterweights 28 and 29 would be proportionately different. Moreover, as will appear hereinafter, in the actual pantograph mechanism the cylinders l5 and I6 are coaxial and their pistons are connected and oppose each other. The counterweight required, therefore, need be only the difference between the actual counterweights needed at 28 and 29 if the system were as shown in Figures 1 and 2.

If now the drum is charged with a batch of aggregates as shown in Figure 1 but with the drum stationary (that is, not revolving), an upward force on all of the pistons of the pantograph mechanism manifests the addition of this load on the trunnions. However, as the proportion of the load carried by the two trunnions has not changed, no action occurs. A pull is merely exerted on the lever member I! by the tug and whifiietree connection 22-23 proportional to the weight of the batch and one-half this pull is exerted on each of the opposite ends of the lever member by the tug and whifiletree connections 25 and 26.

When the drum revolves and the mass is carried laterally over toward the ascending side of the drum as shown in Figure 2, the center of gravity of the mass shifts to the left as indicated and as a consequence the load on the trunnion 8 is proportionately greater than the load on the trunnion 9.

The sum of the loads on the trunnions, however, remains the same. The mill exerted on the lever member ll as a result of the'upward reactions of the pistons l3 and I4 thus is not altered, for while the pressure in the line [9 and under the piston l3 has been increased, the pressure in the line and under the pistonld' has been decreased bya like amount. v

A difierent effect is produced at the cylinders 15 and I6 by this difference in fluid pressure in the lines I!) and 20. Here the increased pressure in the line H! and the corresponding decrease hence has a turning moment effective on the lever member.

To illustrate, consider that the upward pull on point 24 as a result of the sum of the reactions in cylinders I-3 and 14 due to concrete in the drum is one hundred pounds, and that the pull on the whifiletree 25 is fifty-five pounds while' the pull on the whifiietree 26 is forty-five pounds because of the shift in center of gravity. These forces acting on the lever member will cause it to rock clockwise on its fixed pivot l8 until the turning moment on the lever member due to the ten pound difierential between the pulls acting on the opposite ends thereof balances the turning moment applied on the lever member by the one hundred pound pull applied at point 24.

Assuming that the batch in the drum is of the proper consistency, the position which the lever member I! assumes at this time can be utilized to indicate zero or desired consistency on a suitable indicator or gauge so that a shift in the position of the center of gravity due to either wetter or drier consistency will be reflected by motion of the lever member I! about its pivot l8 in one direction or the other; and this motion properly translated to a pointer on a scale or other indicating medium will indicate the variation from the desired consistency and enable the operator to make the necessary correction.

As noted hereinbefore the disclosures of Figures 1 and 2 are purely diagrammatic and are intended only to illustrate the manner in which the forces operate in the system to bring about the desired indication of the shift in the center of gravity. In actual practice, the pantograph board and particularly the lever member I! and the relationship of the cylinders l5 and I 6 is difierent from that shown in Figures 1 and 2.

The actual construction of the pantographboard is as illustrated in Figures 4 and 5. It consists of a supporting panel 30 which may be secured to any suitable support adjacent to the mixer. Being so disposed, the panel 30 is subjected to the vibration of the mixer which has a beneficial effect as will be hereinafter noted.

Secured to the panel 30 is a bracket 3| which supports the fixed pivot IE on which the lever member I! is pivoted. The lever member ll, however, instead of extending to opposite sides of the pivot 18 as in Figures 1 and 2 is of triangular or bell crank formation with one arm substantially horizontal and the other vertical. The upper or outer end of the vertical arm has the whiffietree 23 pivoted thereto at the point 24. The outer end of the horizontal arm has the effect of the differential in reaction in the cylinders l5 and [6 applied thereto by means of a whiflietree 32 pivoted to the lever member at 33 and tugs 34 which connect the whiiiietree with a cross piece 35 which also serves as a counterweight platform. The cross piece 35 is fixed to the pistons or rams of the cylinders l5 and I6 which are opposed.

Inasmuch as it is essential that both sets of cylinders l3 and, and i5 and I6, are securely held in exact coaxiality, a special mounting bracket 36 is provided for each set of cylinders. These brackets are in the nature of channels having spaced flanges 36' between which the cylinders are positioned. Outwardly extending at-' taching flanges 31 on the channels enable the brackets to be bolted to the panel 3%]. Suitable pads are formed on the inner surfaces of the flanges 36' and on the bottom of the channel to enable accurate machining and insure properly located seats for the attaching portions or brackets 38 of the cylinders.

In this manner a simple and very rigid mounting is provided for the cylinders by which absolute nected with the piston of the cylinder 63 remains oil the scale- When the drum is loaded and the mixer is in operation the indication afforded by the pointer 13 will follow changes in the location of the center of gravity of the batch.

Inasmuch as this form of the invention is designed with a view toward its incorporation in pavers which very often are operated on an incline, means are provided for adjusting the pantograph mechanism to compensate for errors which would otherwise existbecause of the angles involved. To this end the tug and whiflietrees by which the pistons or rams of the miniature cylinders are connected with the lever member are provided with adjustments as clearly shown in'Figure 6. By virtue of these adjustments the points of force application to the pantograph lever may be adjusted toward and from its fixed pivot 65.

From the foregoing description, taken in the connection with the accompanying drawings. it will be readily apparent to those skilled in the art that this invention provides a hydraulic control apparatus especially well adapted for use with concrete consistency meters in that it provides a reliably accurate manner of translating changes in force reactions due toa shift in the center of gravity of the batch into indicator motion.

What I claim as my invention is:

1. In an apparatus of the character described: two load responsive means for producing fluid pressure; and a fluid pressure actuated means responsive to said fluid pressure for effecting an indication of the ratio of the loads on said two load responsive means comprising, a pair of hydraulic cylinders having their movable elements acting in the same direction under pressure in the cylinders; means connecting their movable elements so that the forces of said movable elements are added; a lever member; a fixed pivot for the lever member; a connection between said connected movable elements of the cylinders and the lever member at a point spaced from the pivot of the lever member; another pair of hydraulic cylinders having their movable elements connected with the lever member in a manner such that the forces they apply on the lever member are opposed so that a differential in said forces produces a turning moment on the lever memben to rock the lever member on its pivot until said turning moment produced by said differential in forces equals the turning moment placed on the lever member by the sum of the forces of the movable elements of the first mentioned pair of cylinders; and indicator means driven by the lever member.

2. In an apparatus of the character described: a, stationary support; a lever member pivoted on said support; a pair of hydraulic cylinders each having fixed and movable elements; means mounting said cylinders with their axes coaxial and with their movable elements acting in the same direction under pressure in the cylinders; means connecting said movable elements of the cylinders to each other and with the lever member at a point spaced from its pivot so that the sum of the forces of said movable elements is capable of imparting a turning moment on the lever member; another pair of hydraulic cylinders each having fixed and movable elements; means mounting said other pair of hydraulic cylinders with their axes coaxial and with their movable elements acting in opposite directions under influence of pressure in the cylinders; means connecting the movable elements of said other cylinders so that their forces oppose each other; and means connecting the connected movable elements of said other cylinders with the lever member at another point so that a differential in pressure in said other cylinders applies a turning moment on the lever member to oppose any turning moment produced by the forces of the movable elements of said first mentioned cylinders. 1

3. In an apparatus of the character described: a stationary support; a lever member pivoted thereon; a pair of hydraulic cylinders having pistons movable therein; means mounting said cylinders on the stationary support, the pistons of both cylinders acting in the same direction under influence of pressure in the cylinders; a connection between both of said pistons and a point on the lever member spaced from its pivot so that said pistons may impose a turning moment on the lever member; a second pair of hydraulic cylinders having pistons movable therein; means mounting said second pair of hydraulic cylinders on the stationary support with their pistons acting in opposite directions under influence of pressure in said second cylinders; and means for connecting both of the pistons of said second cylinders with another point on the lever member spaced from its pivot so that the turning moment imposed on the lever member by the pistons of said second pair of hydraulic cylinders in consequence to a differential in pressure in said cylinders opposes the turning moment imposed on the lever member by the pistons of the first named cylinders.

4. The apparatus defined in claim 1 characterized by the fact that the two load responsive means have large pressure applying areas while all of the movable elements of the hydraulic cylinders have small pressure applying areas.

5. In an apparatus of the character described: a stationary support; a lever member pivoted thereon; an indicator operable by the rocking motion of the lever member; a hydraulic cylinder fixed on the support, said cylinder having a piston movable therein; a whiflietree pivoted to the lever at a point spaced from its pivot; tugs connecting the whiffletree with the piston of said cylinder so that the force of the piston in response to pressure in the cylinder is transmitted to the lever member to impose a turning moment thereon Whenever the line of force is out of line with the pivot of the lever member; a second hydraulic cylinder mounted on the support, said second cylinder having a piston movable therein; a second whiffietree pivoted to the lever member at another point thereon spaced from its pivot; and tugs connecting said second whiffletree with the piston of said second cylinder so that the force of the piston in said second cylinder in response to pressure in the cylinder is transmitted to the lever member to impose a turning moment on the lever member in opposition to the aforesaid turning moment.

6. Means for indicating the ratio of the loads imposed by the shifting contents of a receptacle on two supports for the receptacle, comprising: a load responsive means interposed between each of the supports and the receptacle; a lever member pivoted to rock about a fixed point; an indicator operable by the rocking motion of the lever member; a stationary cylinder mounted so as to be subjected to the vibration produced by the sh'sittingeof the' reeeptacle contents; 'ar cfose fi-tting:

pistcn -slidabl'e: in the cylinder means connectingge m-see forum-oi said piston 2 of 'the lsecondtzcylmdet: 1m;- poses a turning moment on the leverrmember in oppcsitiori'to :theiaforesaiditumingimoment; and duct? means connecting eaclncyli'nder with one load; responsivea.means ;sos thatdiuidvin:saicliloadresponsive means, cylinderss and; duct means transmitsapressure ximposedlionithe 5103i .;1'.esponsi've' means to thezpis'tonsciofthe two cylinders; the vibration: caused; by ;-the shitting receptacle contents: insuring, nesponsev of the: pistons: to changes in fluid; pressure: notwithstanding. the closeness 'ofztheilr fit inkthe cylinderss I GLENWA Y 'MAXOR JR 

